Convert Seconds to Days
Convert Seconds (s) to Days (d) instantly and accurately.
Conversion Formula
d = s × 1.157407407e-5
About Seconds
The second (s) is the SI base unit of time, defined since 1967 as exactly 9,192,631,770 periods of the caesium-133 ground-state hyperfine transition at 0 K. Caesium fountain clocks realise this to ~10⁻¹⁶ (1 s lost per ~300 million years); optical lattice clocks (Sr, Yb) reach ~10⁻¹⁸. The second links to the metre via the defined speed of light c = 299,792,458 m/s exactly. 1 s = 1,000 ms = 1/60 min.
About Days
A day (d) = exactly 86,400 s. Earth's actual solar day varies ±16 s due to orbital eccentricity and axial tilt (equation of time). Leap seconds (abandoned in UTC after 2035) corrected the TAI-UT1 divergence. Mars's sol = 24 h 39 min 35 s ≈ 88,775 s; a Martian year = 668.6 sols. The day structures circadian biology, tides, and planetary science. 1 day = 86,400 s = 24 h.
Quick Reference Table
| Seconds (s) | Days (d) |
|---|---|
| 1 s | 1.157 × 10-5 d |
| 2 s | 2.315 × 10-5 d |
| 5 s | 5.787 × 10-5 d |
| 10 s | 0.000115741 d |
| 25 s | 0.000289352 d |
| 50 s | 0.000578704 d |
| 100 s | 0.00115741 d |